These templates ({{Birth date}} and {{Birth date and age}}) return a person's date of birth and optionally his/her age. The latter also have the shortcut: {{Bda}}.

Using this template rather than simply inserting the date into articles allows for the inclusion of hidden metadata about the date. This metadata can be used by web browsers and other software tools to extract the details, and display them using some other website or mapping tool, index or search them.

An optional parameter, df, can be set (to "y" or "yes" for example) to display the day before the month. This is primarily used in articles about people from parts of the world where the day precedes the month in a date. Conversely the (unimplemented) parameter mf can be set for month first, currently the default behaviour.